Another nice-to-have: When working with a large stack, I merged the bottom 3 diffs, and still had a few on top. I then kept working at the top of that stack and wanted to create another diff. Submitting this PR triggered an update to all others (unmerged) PRs in the stack, retriggering CI even though code hadn't changed at all. Nbd, but just a bit annoying. Repro:

Submit PR stack
Merge bottom PR(s) with rebase method
gt sync (restacks and updates all local commits to new hashes)
*new code*
gt create; gt submit (updates ALL PRs in the stack, triggering CI for all of them)

I don't have a great solution to this, since it feels like a collision of git's "branch-based" vs graphite's "diff-based" methods colliding.